Molecular biology can be broadly defined as the branch of biology that deals with the formation, structure and function of macromolecules such as nucleic acids and proteins and their role in cell replication and the transmission of genetic information, as well as the manipulation of nucleic acids, so that they can be sequenced, mutated, and further manipulated into the genome of an organism to study the biological effects of the mutation.
The conventional practice of biochemistry and molecular biology can require physical process resources on a scale that are frequently inversely proportional to the size of the subject being studied. For example, the apparatus and process chemistry associated with the preparation and purification of a biological sample such as a nucleic acid fragment for prospective analysis may easily require a full scale bio-laboratory with sterile facilities. Furthermore, an environmentally isolated facility of similar scale may typically be required to carry out the known polymerase chain reaction (PCR) process for amplifying the nucleic acid fragment.
2.1 Microfluidic Systems
“Microfluidics” generally refers to systems, devices, and methods for processing small volumes of fluids. Microfluidic systems can integrate a wide variety of operations for manipulating fluids. Such fluids may include chemical or biological samples. These systems also have many application areas, such as biological assays (for, e.g., medical diagnoses, drug discovery and drug delivery), biochemical sensors, or life science research in general as well as environmental analysis, industrial process monitoring and food safety testing.
One type of microfluidic device is a microfluidic chip. Microfluidic chips may include micro-scale features (or “microfeatures”), such as channels, valves, pumps, reactors and/or reservoirs for storing fluids, for routing fluids to and from various locations on the chip, and/or for reacting fluidic reagents.
However, existing microfluidic systems lack adequate mechanisms for allowing controlled manipulation of multiple fluids except via prescribed flow patterns, hence limiting the practicality with which the systems can be utilized in various chemical or biological assays. This is because real-world assays often require repetitive manipulation of different reagents for various analytical purposes.
Moreover, many existing microfluidic devices are restricted for one specific use and cannot be easily adapted or customized for other applications without being completely redesigned. These devices lack modularity, and therefore cannot share common device components that allow one design to perform multiple functions. This lack of flexibility leads to increased production costs as each use requires the production of a different system.
Furthermore, many existing microfluidic systems lack any means for straightforward end-point assays that are able to easily detect interactions or existence of analytes resulting from the assays. By way of example, visual detection of sample color changes after an assay is often used to evaluate the assay results
Thus, there exists a need for improved microfluidic systems for processing fluids for analysis of biological or chemical samples, and in particular, in the detection and analysis of biologically active macromolecules derived from such samples such as DNA, RNA, amino acids and proteins. It is desired that the systems are mass producible, inexpensive, and preferably disposable. It is desired that the systems be simple to operate and that many or substantially all of the fluid processing steps be automated. It is desired that the systems be customizable, and be modular such that the system can be easily and rapidly reconfigured to suit various applications in which the detection of macromolecules is desired. It is also desired that the systems be able to provide straightforward and meaningful assay results.
Citation or identification of any reference in Section 2, or in any other section of this application, shall not be considered an admission that such reference is available as prior art to the present invention.